Oil Change Filter Question

[FlyingMonkey]

Hey all...

 

It's time again for an oil change, and I have a quick question.  Last time I changed it, I followed a set of instructions from Roger, one of which was to fill the new filter with oil before installing, which I did.  It made a mess when I tipped it up, even though I put a plastic bag around it to minimize it.  I recently read something Roger posted that hinted that it's not really necessary to pre-fill the oil filter -- obviously if I can avoid that mess, I'd like to!

 

So, fill or don't fill the oil filter?

[Rich]

Andy,

 

I've changed my oil three times and never tried to fill the oil filter. I can't find any reference to it in the Rotax maintenance manual.

This is the first time I've heard of trying to do that.

[FlyingMonkey]

Andy,

 

I've changed my oil three times and never tried to fill the oil filter. I can't find any reference to it in the Rotax maintenance manual.

This is the first time I've heard of trying to do that.

 

Then I guess I'm good to go without it!

[Tom Baker]

The old style filter you could fill. The new style you can't fill.

[Anticept]

Wouldn't just pulling the prop through preoil the filter and purge air?

[N751JM]

I just returned from the LSRM-A Maintenance class in Corning CA (an excellent class BTW).  This exact topic came up and the instructor (Brian Carpenter, very knowledgable) commented that it is NOT in the Maintenance Manual to fill the filter with oil during an oil and filter change and he's had an on-going "discussion" with someone at Rotax who claimed it is "common knowledge" to do this.  If I learned one thing in the class it was "follow the manual".  So I changed the oil, under Brian's supervision, and did not pre-fill the filter.  The manual does talk about pulling the prop through, which I did.  Had a few moments of low oil pressure on start but then all returned quickly to normal.

[FlyingMonkey]

So, to be clear:

 

1) Burp engine to get oil back to reservoir

 

2) Empty oil from reservoir

 

3) Remove filter / Install new filter

 

4) Check mag plug

 

5) Reinstall & Safety wire mag plug

 

6) Refill oil -- 3 quarts

 

7) Turn prop ten rotations or so to circulate oil

 

Does that sound about right? 

[Anticept]

3 liters, not 3 quarts .

 

Run engine so it's nice and warm (makes oil easier to flow), turn prop, drain oil, turn prop again to make sure you got it all out of the sump (though it can be argued this is kinda overkill). scratch that last part. Not a good idea to crank while oil system is open.

[FlyingMonkey]

3 liters, not 3 quarts .

 

Run engine so it's nice and warm (makes oil easier to flow), turn prop, drain oil, turn prop again to make sure you got it all out of the sump (though it can be argued this is kinda overkill).

 

I thought Roger said if you turn the prop after draining the oil you will pump air in and have to do a full purge to avoid lifter damage...  :unsure:

 

And if I do this warm, aren't I going to burn myself on filters, oil, and exhausts?

 

Quarts, liters, whatever.  

[Anticept]

I thought Roger said if you turn the prop after draining the oil you will pump air in and have to do a full purge to avoid lifter damage...  :unsure:

 

And if I do this warm, aren't I going to burn myself on filters, oil, and exhausts?

 

Quarts, liters, whatever.  

 

You know, that might be true! I know I've been told that lines themselves shouldn't be disconnected and drained because of that issue, but I had not heard anything about turning the prop. I would think the air would not be pumped easily at all by the oil pump. Till I get word on it, I'm going to stop doing that!

 

It's typical to do oil changes with hot oil. With the cowling off, things actually do cool off pretty quick, and you'll be using tools anyways. I've had hot oil get on my hands, and it's definitely uncomfortable, but I wasn't burned yet.

[N751JM]

My 2 cents - you shouldn't be guessing at this, the one thing I learned in the LSRM class was - follow the manual.  For my CTLS with the Rotax 912ULS, the oil change procedure is on page 49  of the Line Maintenance Manual (there is also a Service Instruction referenced: SI-912-010 so you should read that also).

 

First step says -

NOTES: Run engine to warm oil before beginning oil change procedure.

 

There is a notice part way down the page:

 

NOTICE The engine must not be cranked when the oil system is open.  When the crankshaft was turned, then the oil system must be purged.

 

When inspecting the magnetic plug, do you know what level of accumulation of metal chips is acceptible?  That's on page 59 and 60.

 

If you have a different engine, you'll want to grab the latest manual and SI's for that engine - all are available on the Rotax web site. 

[Jacques]

http://legacy.rotaxowner.com/si_tb_info/serviceinfo/si-912-010.pdf

 

working on engine = looking at Maintenance manual

 

in this case...Line Maintenance Manual, chapter 12 section 11.2)

912 oil change.pdf

[Anticept]

I checked all the applicable manuals, the mentioning of air getting into the system is kinda just small footnotes, talking about not disconnecting lines or leaving the oil filter off for too long. Found the note about not cranking the engine in section 12-00-00. Normally i am using and referencing the checklist, but duly noted, and thanks!

 

One question though. You can take the engine to negative g's for 5 seconds (ops manual, 10.1.1 number 3). Why the heck is that?! I am pretty sure you will suck a lot more air doing that than cranking by hand...

[Doug G.]

Is it only ten turns after the change? I thought it was more. I could go get my books, but I know someone will have the answer at hand.

[Tom Baker]

So, to be clear:

 

1) Burp engine to get oil back to reservoir

 

2) Empty oil from reservoir. Re-install drain plug with new gasket and add the first liter of oil.

 

3) Remove filter / Install new filter

 

4) Check mag plug

 

5) Reinstall & Safety wire mag plug

 

6) Refill oil -- 3 quarts Add remaining oil

 

7) Turn prop ten rotations or so to circulate oil

 

Does that sound about right? 

Andy, your list is OK, but I added a little in red. The reason I do the oil this way is because if I get called away or interupted there is oil over the pick up tube in the tank.

[FlyingMonkey]

Andy, your list is OK, but I added a little in red. The reason I do the oil this way is because if I get called away or interupted there is oil over the pick up tube in the tank.

 

Thanks Tom, not a bad idea!

[Tom Baker]

One other thing, and I know this goes against what Roger says. The magnetic plug is a 100hr check item, and listed separately from the oil change. If I am doing 50 hour oil changes I only check it every other time. I do check it annualy, because the annual uses the 100 hour checklist. I think over sampling can mask a problem instead of showing a problem.

[Doug G.]

Makes sense to me.

[FlyingMonkey]

One other thing, and I know this goes against what Roger says. The magnetic plug is a 100hr check item, and listed separately from the oil change. If I am doing 50 hour oil changes I only check it every other time. I do check it annualy, because the annual uses the 100 hour checklist. I think over sampling can mask a problem instead of showing a problem.

 

Good point...I checked it last time (50hrs ago), I'll leave it be this time.

[azleejay]

Where are you guys getting your filters and crush washers?

Thx

Lee

[FlyingMonkey]

I bought a couple from California power systems.

[sandpiper]

My mag plug gets inspected at every oil change which I do at 40 hours or 4 months whichever comes first. But, it takes me 10 minutes by the time I find the right tools, look up the torque, and then have to safety wire it twice because I tried to save and inch of wire on the first try. :wacko: Then there is the mess of oil to clean out of the radiators - not really since I figured out long ago how not to make a mess.

[WmInce]

. . . "since I figured out long ago how not to make a mess. :)" . . .

 

Would you mind expanding upon that a little?  For the sake of us messy Rotax newcomers.    . . .

[FlyingMonkey]

The mag plug is to be checked at every oil change as specified in the SB's. The reason you see it at 100 hrs. is Rotax allows (not good judgement and not taught in class) oil to be used up to 100 hrs. If you change oil at 50 hrs. that is where you check it. If you change oil at 75 hrs. that is where you check it. The mag plug is supposed to be checked at the annual which is where many change the oil anyway. Checking the mag plug can not cause you problems and may find the beginning of an issue before it gets 100 hrs. on its way. Many gearbox ills can be seen early and make repairs simple and cheap. All of your engine oil passes by the mag plug. Why would you skip this step since it only takes 5 minutes start to finish and may save you money? 

Here is more food for thought to muddy your water. Technically Rotax wants the oil changed at annual even if it was done 15 hrs ago. 

 

Look at it this way. If I told you it was going to cost you $600+ to fix your gearbox for something that may have cost $50 for a re-shim would not have 5 minutes been worth that early on? That's a $120 per minute. I'm not sure I understand why so many try to get out of the easy maint. that may save money down the road with an early warning.

 

 

Andy,

 

It isn't over sampling, it's an early warning system.

 

 

Thanks Roger.  I had planned to check it every change, but the argument of "you might not be able to see accumulation at 50hrs" makes some sense.  If best practice is to always check it, that is what I'll do.

[Tom Baker]

Roger and all,

I too have Rotax training, and I am scheduled to do recurrent training next month. The SB that he mentions is this one. http://legacy.rotaxowner.com/si_tb_info/serviceb/sb-912-051ul.pdf Please read the SB. For most engines this was a one time required inspection, and you then follow the rotax inspection schedule. For the 164 ULS engines the SB says "the plug must be checked at mandentory oil changes". The last time I looked, if running auto fuel the mandetory oil change interval was 100hrs.

 

If you want do the check that's OK, what I do is follow the information provided by Rotax.